Chloroform 2018 Update

Project ID

2673

Category

IRIS

Added on

Jan. 12, 2018, 4:44 a.m.

Search the HERO reference database

Query Builder

Search query
Journal Article

Abstract  OBJECTIVE: To investigate the immunosuppressive potential of Pluchea lanceolata 50% ethanolic extract (PL) and its bioactive chloroform fraction (PLC).

MATERIALS AND METHODS: Preliminary screening of the Pluchea lanceolata 50% ethanolic extract (PL) was carried out with basic models of immunomodulation, such as, the humoral antibody response (hemagglutination antibody titers), cell-mediated immune response (delayed-type hypersensitivity), skin allograft rejection test, in vitro (C. albicans method), and in vivo phagocytosis (carbon clearance test). The extract was then fractionated with chloroform, n-butanol, and water to receive the respective fractions by partitioning. These fractions were employed for flow cytometry to study the T-cell specific immunosuppressive potential of these fractions.

RESULTS: Oral administration of PL at doses of 50 to 800 mg/kg in mice, with sheep red blood cells (SRBC) as an antigen, inhibited both humoral and cell-mediated immune responses, as evidenced by the production of the circulating antibody titer and delayed-type hypersensitiviy reaction results, respectively, and the immune suppression was statistically significant (P < 0.01) in Balb/C mice. PL also decreased the process of phagocytosis both in vitro (31.23%) and ex vivo (32.81%) and delayed the graft rejection time (30.76%). To study the T-cell-specific activities, chloroform, n-butanol, and water fractions from P. lanceolata were tested for T-cell specific immunosuppressive evaluation, wherein only the chloroform fraction (PLC) showed significant (P < 0.01) suppression of CD8+ / CD4+ T-cell surface markers and intracellular Th1 (IL-2 and IFN-(Y)) cytokines at 25 - 200 mg/kg p.o. doses. PLC, however, did not show significant suppression of the Th2 (IL-4) cytokine.

CONCLUSION: The findings from the present investigation reveal that P. lanceolata causes immunosuppression by inhibiting Th1 cytokines.

WoS
Journal Article

Abstract  Purpose: To investigate the T cell inhibition potential of 50% ethanol extract of Cyperus scariosus (CS) and its bioactive chloroform fraction (CSC). Methods: The preliminary screening of the extract was carried out by humoral antibody response and delayed-type hypersensitivity models employing sheep red blood cells (SRBC) as the antigen. Further, the extract was studied by skin allograft rejection test, and phagocytosis - in vitro and ex vivo-by C. albicans method and carbon clearance test, respectively. The extract was fractionated with chloroform, n-butanol and water, and then used to investigate the T-cell specific immunosuppressive potential of these fractions by flow cytometry. Results: On p.o. administration, CS inhibited both humoral and cell-mediated immune responses significantly (p < 0.01) by suppressing primary (26.8 %) and secondary (29.7 %) antibody titres, and also inhibited cell-mediated delayed type hypersensitivity (DTH) immune response (45.9 %) at 600 mg/kg dose, phagocytosis-both in vitro (37.4 %) and ex vivo (37.8 %) - and delayed the graft rejection time (45.8%), thus confirming marked immunosuppression. Out of the three isolated fractions, only the chloroform fraction significantly (p < 0.01) suppressed CD8+/ CD4+ T cell surface markers (14.0/25.3 %) and intra-cellular Th1 cytokines, viz, IL-2 (34.4 %), and IFN-gamma (34.7 %), compared to cyclosporine-A (5), a standard T cell inhibitor (53.6 %) which was given to Balb/C mice at 200 mg/kg dose. CSC did not significantly (p < 0.01) suppress Th2 (IL-4) system. Conclusion: The findings from this investigation reveal that C. scariosus causes immunosuppression by inhibiting Th1 cytokines.

Journal Article

Abstract  In this work, the experimental and theoretical study on the molecular structure and vibrational spectra of 2,4,5-trichloroaniline (C(6)H(4)NCl(3), abbreviated as 2,4,5-TClA) were studied. The FT-IR and FT-Raman spectra were recorded. The molecular geometry and vibrational frequencies in the ground state were calculated by using the Hartree-Fock (HF) and density functional theory (DFT) methods (B3LYP) with 6-311++G(d,p) basis set. Comparison of the observed fundamental vibrational frequencies of 2,4,5-TClA with calculated results by HF and DFT indicates that B3LYP is superior to HF method for molecular vibrational problems. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The theoretically predicted FT-IR and FT-Raman spectra of the title molecule have been constructed. A study on the electronic properties, such as HOMO and LUMO energies, were performed by time-dependent DFT (TD-DFT) approach. Besides, molecular electrostatic potential (MEP) and thermodynamic properties were performed. The electric dipole moment (μ) and the first hyperpolarizability (β) values of the investigated molecule were computed using ab initio quantum mechanical calculations. The calculated results also show that the 2,4,5-TClA molecule may have microscopic nonlinear optical (NLO) behavior with non-zero values. Mulliken atomic charges of 2,4,5-TClA was calculated and compared with aniline and chlorobenzene molecules. The (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results.

Journal Article

Abstract  We report on studies of the tailored self-assembly of the perylene diimide derivative, N,N'-ditridecylperylene-3,4,9,10-tetracarboxylic diimide, into structures with fibrous gel-type, one-dimensional, and two-dimensional morphologies. This approach for producing highly ordered nanostructures of well-defined morphologies utilizes a property of π-conjugated molecules to assemble in poor organic solvents due to π-π interaction between the aromatic cores and takes advantage of the temperature dependence of solubility. The morphology control is based on a fine-tuning of anisotropic, intermolecular solute-solute interactions that are attenuated by the solute-solvent interaction in organic solvents of different chemical structure. We discuss the role of light illumination in the self-assembly process as well as application of ultrasonic treatment as a way of mechanical tailoring of morphology. This approach paves the way toward the molecular-scale tailoring of structural properties of organic semiconducting materials for electronic and optoelectronic applications.

Journal Article

Abstract  INTRODUCTION: Effective removal of gutta-percha in endodontic retreatment is a significant factor to ensure a favorable outcome from failed procedures. The purpose of this study was to evaluate the efficacy of a nickel-titanium rotary instrument system with or without a solvent versus stainless steel hand files for gutta-percha removal.

METHODS: Forty extracted human maxillary anterior teeth were prepared and filled. They were divided into 4 groups: Gates-Glidden and K-files, Gates-Glidden and K-files with chloroform, ProTaper Universal rotary retreatment system, and ProTaper Universal rotary retreatment system with chloroform. The operating time was recorded. The teeth were longitudinally sectioned and photographed. The images were analyzed and the filling remnants were quantified by using the IMAGE TOOL software.

RESULTS: With Kruskall-Wallis test, statistical analysis showed that there was no significant difference between the techniques in regard to the amount of the endodontic filling remnants (P < .05); however, the ProTaper Universal rotary retreatment system was faster than the hand files (P < .05).

CONCLUSIONS: All of the techniques proved helpful for the removal of endodontic filling material, and they were similar in material remaining after retreatment, but the ProTaper Universal rotary retreatment system without chloroform was faster.

Journal Article

Abstract  The objective of this study was to evaluate the chemical composition CH3OH-CH2Cl2 (1:1) extract and biological activities of various extracts derived from the aerial parts of the brown marine alga Stoechospermum marginatum (C. Agardh). Gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS) were used to analyze the composition of the essential oil. Total phenolics assay demonstrated a high value in hexane extract (HE), with a lower value for chloroform extract (CE), and the lowest value for methanol extract (ME). DPPH (2,2-diphenyl-1-picrylhydrazyl) assay showed that extracts of S. marginatum possess radical scavenging activity (RSA). Tests of the antioxidant property of the extracts revealed both electron and hydrogen transfer mechanisms. The antibacterial activity of the ME, CE, and HE as well as an ethanol extract was estimated against seven Gram-positive and Gram-negative bacteria. The ethanol extract showed the highest antibacterial activity, and the HE showed the lowest.

Journal Article

Abstract  Soil dissolved organic carbon (DOC) sources and its seasonal dynamics are poorly known. We aimed to determine the contribution of plant and soil organic matter (SOM) to size classes of DOC in a field experiment with C3 to C4 vegetation change on two soil types through different seasons. Stable isotope ratios of DOC size classes were measured using size exclusion chromatography (SEC) coupled online to liquid chromatography-isotope ratio mass spectrometry (LC-IRMS). SEC resolved DOC into three size classes: very high molecular weight/vHMW (> 10 kDa), high molecular weight/HMW (0.4-10 kDa), and low molecular weight/LMW (< 0.4 kDa). HMW DOC was most abundant in all seasons, soil types, and depths. In contrast, vHMW DOC was only seen postsnowmelt in upper 20 cm and was mainly (87 ± 9%) plant-derived. Through all seasons, HMW and LMW DOC had less than 30% recent plant contribution. Similar size range and source of DOC size classes and soil chloroform fumigation extracts suggest microbial origin of DOC. Thus, microbial SOM recycling is an important process in DOC production. We suggest that DOC molecules get partitioned manifold between soil solution and the mineral matrix (chromatography), thereby getting constantly decomposed, altered, or produced anew by soil microorganisms (reactive transport).

Journal Article

Abstract  In the present study, the effect of DG chloroform root extract was assessed on isolated rat heart and in-vitro antioxidant models. Ischemia reperfusion injury was experimentally induced by using Langendroff apparatus. The free radical scavenging potential was studied in vitro by using different antioxidant models such as DPPH, super oxide scavenging activity, hydroxide scavenging activity and nitric oxide scavenging activity. Both experimental approaches not only substantiate its antioxidant potential but also the cardio-protection imparted by the extract. The cardio-stimulatory effects were investigated for the extract by treating it as a pre-conditioning agent against myocardial ischemia reperfusion injury. The improved antioxidant status of the myocardium indirectly predicts reduced oxidative stress mediated by ischemic reperfusion with evident reduction of infarct size determined by cardiac marker protein. These findings indicate that DG chloroform root extract may possess therapeutic potential against ischemia reperfusion injury.

Journal Article

Abstract  Surface grafting of crystalline and ultrafine cellulose nanofibrils with poly(ethylene glycol) (PEG) chains via ionic bonds was achieved by a simple ion-exchange treatment. The PEG-grafted cellulose nanofibrils exhibited nanodispersibility in organic solvents such as chloroform, toluene, and tetrahydrofuran. Then, the PEG-grafted cellulose nanofibril/chloroform dispersion and poly(L-lactide) (PLLA)/chloroform solution were mixed, and the PEG-grafted cellulose nanofibril/PLLA composite films with various blend ratios were prepared by casting the mixtures on a plate and drying. The tensile strength, Young's modulus, and work of fracture of the composite films were remarkably improved, despite low cellulose addition levels (<1 wt %). The highly efficient nanocomposite effect was explained in terms of achievement of nanodispersion states of the PEG-grafted cellulose nanofibrils in the PLLA matrix. Moreover, some attractive interactions mediated by the PEG chains were likely to be formed between the cellulose nanofibrils and PLLA molecules in the composites, additionally enhancing the efficient nanocomposite effect.

Journal Article

Abstract  This study investigated optimizing the formulation parameters for encapsulation of a model mucinolytic enzyme, α-chymotrypsin (α-CH), within a novel polymer; poly(ethylene glycol)-co-poly(glycerol adipate-co-ω-pentadecalactone), PEG-co-(PGA-co-PDL) which were then applied to the formulation of DNase I. α-CH or DNase I loaded microparticles were prepared via spray drying from double emulsion (w(1)/o/w(2)) utilizing chloroform (CHF) as the organic solvent, L-leucine as a dispersibility enhancer and an internal aqueous phase (w(1)) containing PEG4500 or Pluronic(®) F-68 (PLF68). α-CH released from microparticles was investigated for bioactivity using the azocasein assay and the mucinolytic activity was assessed utilizing the degradation of mucin suspension assay. The chemical structure of PEG-co-(PGA-co-PDL) was characterized by (1)H NMR and FT-IR with both analyses confirming PEG incorporated into the polymer backbone, and any unreacted units removed. Optimum formulation α-CH-CHF/PLF68, 1% produced the highest bioactivity, enzyme encapsulation (20.08±3.91%), loading (22.31±4.34 μg/mg), FPF (fine particle fraction) (37.63±0.97%); FPD (fine particle dose) (179.88±9.43 μg), MMAD (mass median aerodynamic diameter) (2.95±1.61 μm), and the mucinolytic activity was equal to the native non-encapsulated enzyme up to 5h. DNase I-CHF/PLF68, 1% resulted in enzyme encapsulation (17.44±3.11%), loading (19.31±3.27 μg/mg) and activity (81.9±2.7%). The results indicate PEG-co-(PGA-co-PDL) can be considered as a potential biodegradable polymer carrier for dry powder inhalation of macromolecules for treatment of local pulmonary diseases.

Journal Article

Abstract  Chloroform (CF) is largely produced by both anthropogenic and natural sources. It is detected in ground and surface water sources and it represents the most abundant halocarbon in the atmosphere. Microbial CF degradation occurs under both aerobic and anaerobic conditions. Apart from a few reports describing the utilization of CF as a terminal electron acceptor during growth, CF degradation was mainly reported as a cometabolic process. CF aerobic cometabolism is supported by growth on short-chain alkanes (i.e., methane, propane, butane, and hexane), aromatic hydrocarbons (i.e., toluene and phenol), and ammonia via the activity of monooxygenases (MOs) operatively divided into different families. The main factors affecting CF cometabolism are (1) the inhibition of CF degradation exerted by the growth substrate, (2) the need for reductant supply to maintain MO activity, and (3) the toxicity of CF degradation products. Under anaerobic conditions, CF degradation was mainly associated to the activity of methanogens, although some examples of CF-degrading sulfate-reducing, fermenting, and acetogenic bacteria are reported in the literature. Higher CF toxicity levels and lower degradation rates were shown by anaerobic systems in comparison to the aerobic ones. Applied physiological and genetic aspects of microbial cometabolism of CF will be presented along with bioremediation perspectives.

Journal Article

Abstract  In this bacterial RNA isolation protocol, an "RNA-protective" treatment is followed by lysozyme digestion of the peptidoglycan component of the cell wall. EDTA promotes the loss of the outer membrane of Gram-negative bacteria and allows the lysozyme better access to the peptidoglycan. Cells begin to lyse during digestion in hypotonic lysozyme buffer and lysis is completed by sodium dodecyl sulfate (SDS) and hot phenol:chloroform:isoamyl alcohol (PCA) extraction. SDS and hot phenol disrupt membranes, denature protein (including RNase), and strip proteins from RNA. The separation of the organic phase from the aqueous phase is achieved using Phase Lock Gel, an inert material with a density intermediate between the organic and aqueous samples. The sample is split into three phases: from bottom to top, these are phenol and chloroform (organic phase), the inert gel with the interface material, and the aqueous phase with the RNA. The gel acts as a physical barrier between the sample and the organic phase plus interface. Following organic extraction, the RNA is concentrated by ethanol precipitation.

Journal Article

Abstract  The purpose of this study was to improve in vitro dissolution and in vivo absorption of itraconazole (ITZ), a poorly water-soluble drug, by means of novel pectin-based nanoparticles prepared from nanoemulsion templates. Nanoemulsion templates were prepared by a high-pressure homogenization using pectin (i.e., 0.5-3.0%w/w low-methoxyl pectin (LMP), amidated low-methoxyl pectin (ALMP), or high-methoxyl pectin (HMP)) as an emulsifier and chloroform as an oil phase. HMP provided good oil-in-water emulsions with ITZ loaded in the oil phase. The chloroform in nanoemulsions was then removed to produce the suspensions of nanoparticles dispersed in water phase. After lyophilization, the dried core-shell nanoparticles with good properties in terms of redispersibility, dissolution, and stability were obtained. The alteration of ITZ crystallinity was clearly observed from powder X-ray diffractogram while no interaction between ITZ and pectin was found in the nanoparticles. The ITZ-loaded nanoparticles showed high percent drug dissolved, especially those prepared from HMP, and could maintain their good dissolution properties even after 6-month storage. The in vivo absorption study in fasted rats demonstrated that pectin-based nanoparticles prepared from nanoemulsion templates could improve absorption of ITZ, that is, 1.3-fold higher than the ITZ commercial product (p<0.05). Pectin type highly influenced the dissolution properties and also in vivo plasma profile. These findings suggested that HMP-based nanoparticles seem to be a promising formulation due to their high AUC(0-24h) and C(max).

Journal Article

Abstract  Multiple lines of evidence for indicating factors associated with the sources, transport, and fate of chloroform and three other trihalomethanes (THMs) in untreated groundwater were revealed by evaluating low-level analytical results and logistic regression results for THMs. Samples of untreated groundwater from wells used for drinking water were collected from 1996-2007 from 2492 wells across the United States and analyzed for chloroform, bromodichloromethane, dibromochloromethane, and bromoform by a low-level analytical method implemented in April 1996. Using an assessment level of 0.02 μg/L, chloroform was detected in 36.5% of public-well samples and 17.6% of domestic-well samples, with most concentrations less than 1 μg/L. Brominated THMs occurred less frequently than chloroform but more frequently in public-well samples than domestic-well samples. For both public and domestic wells, THMs occurred most frequently in urban areas. Logistic regression analyses showed that the occurrence of THMs was related to nonpoint sources such as urban land use and to point sources like septic systems. The frequent occurrence and concentration distribution pattern of THMs, as well as their frequent co-occurrence with other organic compounds and nitrate, all known to have anthropogenic sources, and the positive associations between THM occurrence and dissolved oxygen and recharge indicate the recycling of water that contains THMs and other anthropogenic contaminants.

Journal Article

Abstract  In the present study, a new approach which uses immunoaffinity column clean-up combined with dispersive liquid-liquid microextraction (DLLME) is proposed for the preconcentration of ultra trace amounts of aflatoxins (B₁, B₂, G₁ and G₂). The aflatoxins are then determined using a high-performance liquid chromatography coupled with fluorescent detector. Samples are extracted by immunoaffinity column (IAC) clean-up, and their eluents are used as dispersants of the subsequent DLLME, for further enrichment of aflatoxins. Various parameters (the type of elution solvent, the type and volume of extraction solvent and disperser solvent, extraction time, and centrifugation time) that affect the efficiency of the two steps are optimized. Under the optimum conditions (extraction solvent: 120 μL of chloroform, disperser solvent: 500 μL of acetonitrile, sample pH: 7.4, centrifugation time: 3 min), the calibration for B₁, B₂, G₁ and G₂ was found to be linear with coefficient of estimation (R²) of 0.9994, 0.9976, 0.9989, 0.9973 respectively and the limit of detection (LOD) was between 1.1 × 10⁻⁴ to 5.3 × 10⁻³ ng mL⁻¹ (3σ(b)/m, n=9). The recoveries at the two spiked levels ranged from 96.0 to 110.0% and the relative standard deviation (RSD) was less than 7.8% (n=9). The results show that dispersive liquid-liquid microextraction combined with HPLC is a selective, simple, sensitive, and effective analytical method for the preconcentration and determination of ultra trace amounts of aflatoxins. The proposed method was applied for preconcentration and determination of B₁, B₂, G₁ and G₂ aflatoxin in edible oils. Analysis of aflatoxins in FAPAS test material showed that the proposed method has good accuracy.

Journal Article

Abstract  Chloroform (CF, CHCl(3)) is a recalcitrant and toxic environmental pollutant. In this communication we report for the first time a microbial community capable of complete CF dechlorination by metabolic processes. Cultures derived from subsurface soil (3.5 m) could sustain complete dechlorination of CF at levels of least 360 µM at a rate of 40 µM per day. Scrutiny of CF dechlorination revealed two metabolic processes at work. First, CF was respired to dichloromethane (DCM, CH(2) Cl(2)), which was then fermented to acetate, hydrogen and carbon dioxide. Elevated hydrogen partial pressures were found to inhibit the fermentation process. Interspecies hydrogen transfer was observed in the form of methanogenesis and acetogenesis. This suggests that the dechlorination process required syntrophic partners to maintain low hydrogen partial pressures. (13)C-labelled DCM was employed to help elucidate the chemistry of the process and identify bacterial community members involved. CF respiring cultures, where emulsified vegetable oil was supplied as the electron donor and DCM fermenting cultures, where DCM was supplied as the sole organic carbon source were studied separately. Pyrosequencing of these cultures revealed Dehalobacter lineages as a predominant community member in both. Subsequent growth experiments confirmed that the proliferation of Dehalobacter was linked directly to both the dehalorespiration and dehalofermentation processes.

Journal Article

Abstract  BACKGROUND: San-Huang-Xie-Xin-Tang (SHXXT) decoction, a traditional Chinese medicine containing Rhei rhizome, Coptidis rhizome, and Scutellariae radix, is widely used in hepatoprotective therapy. However, preparation of the decoction requires addition of boiling water that causes loss of numerous effective components.

METHODS: To improve the bioavailability of the decoction, nanoscale SHXXT was developed. Chloroform-induced liver injury and hepatic stellate cell activity in mice were used to demonstrate the hepatoprotective characteristics of nanoscale SHXXT decoction.

RESULTS: Liver/body weight ratio and serum aspartate and alanine aminotranferase levels were recovered by the nanoscale SHXXT. TIMP-1 gene expression was inhibited and MMP-2 gene expression was accelerated in activated hepatic stellate cells.

CONCLUSION: Nanoscale SHXXT decoction prepared in room temperature water could have preserved hepatoprotective ability. The results of this study indicate that nanoscale SHXXT could be extracted easily. The simple preparation of this herbal decoction is more convenient and energy-efficient.

Journal Article

Abstract  A multiresidue method was developed based on extraction of 10 g sample with 10 mL acetonitrile and subsequent liquid-liquid partitioning formed by adding 4 g MgSO₄ plus 1 mL chloroform. During the partitioning process, the extraction recoveries of polar analytes were found to be essentially determined by the acetonitrile content in the aqueous phase. The use of MgSO₄ gave the least acetonitrile left in the aqueous phase (lower than 5%) and thus promoting complete partitioning of analytes into the organic phase. At the same time, removal of water from the acetonitrile phase was achieved by adding only a small amount of chloroform with no influence on the acetonitrile content in the aqueous phase, thus leading to decreasing the co-extraction of polar matrix components. The most complete mutual separation of acetonitrile and water was achieved by the joint use of MgSO₄ and chloroform and thus the optimal extraction recovery and analytical selectivity were obtained simultaneously. The new method, with higher recoveries of polar analytes, better analytical selectivity and simpler manipulation, is a claimed improvement to the original QuEChERS method. The proposed method was finally validated by the determination of 20 pesticides in a mixed food matrix by using liquid chromatography tandem mass spectrum (LC-MS/MS). Acceptable linearity, sensitivity, recovery, precision and selectivity results were obtained.

Journal Article

Abstract  Spherical agglomerates of benzoic acid have been successfully prepared by semi-batch, agitated vessel, drowning-out crystallization in water-ethanol-toluene mixtures. Benzoic acid is dissolved in ethanol, toluene is added and this mixture is fed at constant rate to the agitated crystallizer containing water. The influence of the amount of bridging liquid and the feeding rate on the product particle size distribution, morphology, and mechanical compression characteristics have been investigated. Compression characteristics for single agglomerates are compared with data on bed compression. With increasing amount of bridging liquid the particle size and strength increases and morphology improves. Particle size decreases and the fracture force increases with increasing feeding rate but the morphology remains unchanged. Using toluene as opposed to chloroform as the bridging liquid leads to improved product properties. Experiments have also been performed to reveal the mechanisms of the formation of the agglomerates. The results show that along the course of the process the properties of the particles change gradually but substantially. Particle size and number increases along with increasing feed. The spherical shape does not appear immediately but develops gradually, and is shown to be very much the result of the agitation of the slurry.

Journal Article

Abstract  OBJECTIVE: To establish an effective phenol-chloroform method coupled with paramagnetic particle method for human DNA extraction from maggot crop contents in STR genotyping.

METHODS: Human DNA was extracted from the maggot crop contents using phenol-chloroform method and purified by paramagnetic particle method. DNA was quantified by PCR with Quantifiler Human DNA Quantification Kit using 7500 real-time fluorescence quantitative PCR instrument. PCR products were genotyped by AmpFlSTR Identifiler PCR Amplification Kit using 3130XL-Avant genetic analyzer.

RESULTS: The template DNA yield by the method described were increased at least 2 times than the phenol-chloroform extraction method alone. All of the full 16 STR profiles could be obtained with the samples extracted by this method when the DNA yield reached (0.218 +/- 0.041) ng/microL.

CONCLUSION: Phenol-chloroform method coupled with paramagnetic particle method can effectively increase the sensitivity of STR analysis of human DNA recovered from maggot crop contents and is a valuable tool for forensic entomology.

Journal Article

Abstract  DNA isolation from some fungal organisms of agronomic importance is difficult because they have cell walls or capsules that are relatively unsusceptible to lysis. We have developed a fast DNA isolation protocol for Fusarium oxysporum, which causes fusarium wilt disease in more than 100 plant species, and for Pyrenochaeta terrestris, which causes pink root in onions. This protocol was based on the sodium dodecyl sulfate/phenol method, without beta-mercaptoethanol and without maceration in liquid nitrogen; it uses phenol/chloroform extraction to remove proteins and co-precipitated polysaccharides. The A(260/280) absorbance ratios of isolated DNA were around 1.9, suggesting that the DNA fraction was pure and may be used for further analysis. Additionally, the A(260/230) values were higher than 1.8, suggesting negligible contamination by polysaccharides. The DNA isolated by this protocol is of sufficient quality for molecular applications; this technique could be applied to other organisms that have similar substances that hinder DNA extraction.

Journal Article

Abstract  OBJECTIVE: To evaluate a strategy of using TF siRNA loaded in a novel external stent prepared by hybrid ultrafine fibrous membrane consisting of PLGA/Chitosan nanoparticles as a therapy for vein graft disease.

METHODS: Hybrid ultrafine fibrous membranes consisting of PLGA/Chitosan nanoparticles were fabricated via a specially designed electrospinning setup. After soaking in chloroform to dissolve PLGA, the amount of chitosan in the hybrid membranes was determined. The water uptake of the hybrid ultrafine fibrous membranes was investigated by incubation in phosphate buffer solution. Right jugular vein-carotid artery interposition grafting models in Sprague-Dawley rats were randomly divided into five groups:Group A (external stent consisting of PLGA/CS-TFsiRNA nanoparticles), Group B (external stent consisting of PLGA/CS-Stealth(TM) RNAi negative control nanoparticles), Group C (external stent consisting of PLGA/CS blank nanoparticles), Group D (external stent consisting of PLGA), Group E (without perivenous external stent). BLOCK-iT(TM) Fluorescent Oligo was used to confirm its stability and successful transfer into the vein graft wall. The vein grafts were harvested at 1, 3, 7, 14, 28 d after operation, respectively. The TF protein expression of vein grafts was analyzed by Western blot and immunochemistry at 1, 3, 7 d after operation, respectively. The expression of proliferating cell nuclear antigen (PCNA) was identified by immunochemistry methods. The thickness of neointima at 28 d was calculated by computer imaging analysis system.

RESULTS: The PLGA and CS amount in PLGA/Chitosan nanoparticles membranes could be well controlled by adjusting the flow rate for electrospinning of PLGA and chitosan nanoparticles, respectively. Because of the introduction of chitosan, which is a naturally hydrophilic polymer, the hybrid membranes exhibited good water absorption properties. BLOCK-iT(TM) Fluorescent Oligo could be detected in the graft wall even 12 days after operation. The expression of TF protein in Group A was significantly less than that in control groups at 3 d after operation (P < 0.05, 0.40 +/- 0.03 vs 0.75 +/- 0.01, 0.75 +/- 0.05, 0.77 +/- 0.07) and at 7 d after operation (P < 0.05, 0.30 +/- 0.03 vs 0.84 +/- 0.05, 0.86 +/- 0.06, 0.85 +/- 0.06). The expression of PCNA in Group A decreased significantly in comparison with control groups at 14 d after operation (P < 0.01, 13.0% +/- 2.6% vs 25.0% +/- 2.8%, 24.2% +/- 3.9%, 24.0% +/- 4.1%, 44.8% +/- 3.7%). The thickness of neointima at 28 d after grafting in Group A was significantly less than the untreated group (P < 0.01, 18.8 microm +/- 2.9 microm vs 38.7 microm +/- 5.0 microm, 37.3 microm +/- 3.6 microm, 37.2 microm +/- 2.6 microm, 67.5 microm +/- 4.8 microm).

CONCLUSION: The novel external stent prepared by hybrid ultrafine fibrous membrane consisting of PLGA/Chitosan nanoparticles inhibits early neointima formation in rat vein grafts. This strategy may be a practicable and promising form of gene delivery against vein graft failure.

Journal Article

Abstract  An interesting interfacial redox method is developed for the preparation of Au nanoparticles of various shapes in organic medium using Au seeds in aqueous medium without using phase-transfer reagent. The conversion, stabilization, and the transfer of gold nanoparticles to the organic phase is accomplished using the reducing and solubility properties of poly(o-methoxy aniline) in chloroform. The preparatory method is simple, and the Au nanoparticles are free from excess oxidant and external stabilizer. The characterizations of the metal nanoparticles are made using transmission electron microscopy, UV-vis spectra, electron diffraction and energy-dispersive X-ray techniques. Au nanoparticles of various shapes, for example, hexagonal, pentagonal, triangular, rod-shaped, etc. are produced together. A mechanism of the formation of differently shaped nanoparticles is proposed from catalytic reduction of Au(3+) ion by POMA on the Au seed surface followed by the growth of nanoparticles from the exposed Miller planes of seed surfaces.

Journal Article

Abstract  Iron-based degradative solidification/stabilization (DS/S-Fe(II)) is a modification of conventional solidification/stabilization (S/S) that incorporates degradative processes for organic contaminant destruction with immobilization. This study investigated the effectiveness of a binder mixture of Portland cement and slag in a DS/S-Fe(II) system to treat trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), vinyl chloride (VC), trichloromethane (CF), and dichloromethane (MC), which are major chlorinated hydrocarbons contained in waste oils and waste organic solvents. For TCE, 1,1-DCE, and VC, degradation experiments were conducted using three different binder combinations with Fe(II) (cement/Fe(II), slag/Fe(II), and cement/slag/Fe(II)). When cement and slag were mixed at a 1:1 ratio (% wt), the TCE and 1,1-DCE dechlorination rate was enhanced compared to that when cement or slag was used alone with Fe(II). Also, batch experiments were conducted in the solid phase consisting of cement, slag, sand, and Fe(II) to treat liquid wastes that contain chlorinated compounds at high concentrations. TCE was completely removed after 5 days in the cement/slag/sand/Fe(II) system, in which the initial TCE concentration was 11.8mM, with Fe(II) concentration of 565 mM. While the CF concentration was decreased by 95% after 5 days when the initial CF and Fe(II) concentration was 0.25 mM and 200 mM, respectively. However, MC was not degraded with the cement/slag/Fe(II) system.

Journal Article

Abstract  The ability of two heteroditopic calix[4]diquinone receptors to transport a KCl ion-pair and a dopamine zwitterion through a water-chloroform interface was investigated via molecular dynamics (MD) simulations. Gas-phase conformational analysis has been carried on KCl and dopamine receptor binding associations and the lowest energy structures found in both cases show that the recognition of KCl and dopamine zwitterion occurs through multiple and cooperative N-H...anion and O...cation bonding interactions, with the receptor adopting equivalent folded conformations stabilized by pi-stacking interactions. The unconstrained MD simulations performed on KCl and dopamine complexes inserted in either the chloroform or water phase revealed that receptors are preferentially located at the interface with the hydrophobic tert-butyl groups of the calix[4]diquinone moiety immersed in the chloroform bulk while the polar anion binding cavity is directed toward the water phase. When the KCl complex is placed in chloroform, the release of the ion-pair occurs only after the first contact with the water interface, being a nonsimultaneous event, with the chloride anion leaving the receptor before the potassium cation. The dopamine, via the -NH(3)(+) binding entity, remains bound to the receptor during the entire time of the MD simulation (10 ns). In contrast, when both complexes were inserted in the water bulk, the full release of KCl and dopamine are fast events. The potentials of mean force (PMFs), associated with the migration of the complexes from chloroform to water through the interface, were calculated from steered molecular dynamics (SMD) simulations. The PMFs for the free KCl and zwitterionic dopamine migrations were also obtained for comparison purposes. The transport of KCl from water to chloroform (the reverse path) mediated by the receptor has a free energy barrier estimated in 6.50 kcal mol(-1), which is 3.0 kcal mol(-1) smaller than that found for the free KCl. The transport of dopamine complex along the reverse path is characterized by downhill energy profile, with a small free energy barrier of 6.56 kcal mol(-1).

  • <<
  • 1 of 115
  • >>
Filter Results